Utah Master Esthetician Practice Exam

In which layer of the skin are melanocytes primarily found?

1. Stratum corneum

2. Stratum spinosum

3. Stratum germinativum (basal layer)

4. Stratum granulosum

The correct answer is: Stratum germinativum (basal layer)

Melanocytes are primarily located in the stratum germinativum, also known as the basal layer of the epidermis. This layer consists of a single row of columnar or cuboidal cells that are responsible for the production of new skin cells through a process called mitosis. The melanocytes in this layer produce melanin, the pigment that gives skin its color and protects against ultraviolet (UV) radiation. The placement of melanocytes in the basal layer is crucial because it allows for the direct interaction with the underlying blood supply, facilitating the delivery of nutrients necessary for melanin production. This interaction also helps protect the DNA in keratinocytes from UV damage by distributing melanin granules around the nuclei of those cells. The other layers mentioned do not contain melanocytes in significant numbers. The stratum corneum is the outermost layer and consists primarily of dead keratinized cells. The stratum spinosum is located just above the basal layer and primarily contains keratinocytes that have begun the process of keratinization. The stratum granulosum consists of cells that are transitioning in their state, also primarily keratinocytes, and is where the production of keratohyalin granules occurs, contributing to the skin